Surgical needle

ABSTRACT

In a surgical needle, marks of welding are left as they are on a welded portion between needle and pipe members so that the welded portion has a surface distinguishable from peripheral surfaces of the respective needle and pipe members. The welded portion may be composed of a plurality of peripherally spaced welded parts. In a manufacturing method of the surgical needle, a beam energy is applied from a beam energy emitting arrangement, toward an abutting line between the needle and pipe members, from a direction substantially perpendicular to the needle and pipe members, thereby welding them to each other.

BACKGROUND OF THE INVENTION

The present invention relates to a surgical needle of eyeless type, amethod of manufacturing the needle, and an apparatus for carrying outthe method.

A surgical needle of eyeless type is known, in which a bore is formed ina proximal end of the needle and extends along an axis thereof. An endof a suture is inserted into the bore in the proximal end of the needle,and the proximal end of the needle is then staked, whereby the suturecan be attached to the needle. Usually, there are known two methods ofmanufacturing the surgical needle having the proximal end formed thereinwith the bore.

First one of the two known methods is disclosed in Japanese PatentApplication Laid-Open Nos. 52-111294, 60-170590 and 60-184485, JapanesePatent Publication No. 61-58172,Japanese Utility Model Publication No.56-37918 and Japanese Utility Model Application Laid-Open No. 55-43691,in which a drill or a beam energy is used to form the bore in theproximal end of the surgical needle. It is difficult for the firstmethod, however, to form the small diameter bore correctly along theaxis of the needle which is also small in diameter.

The second method is disclosed in Japanese Utility Model Publication No.28-3184, in which a pipe member is welded to an end face of the proximalend of a needle member. In the second method, since a hollow portion ofthe pipe member can be used as a bore for attaching a suture, thebore-forming operation like the first method is dispensed with. Further,it is easy for the second method to manufacture a small diametersurgical needle having therein a small diameter bore extending along theaxis of the surgical needle. The Japanese utility model does notspecifically describe in what manner the pipe member is welded to theproximal end of the needle member. At that time, however, welding haspractically been performed in the following manner. That is, the pipemember has been welded to the proximal end of the needle member by meansof a so-called butt welding, in which an end face of the pipe member isbutted under pressure against an end face of the proximal end of theneedle member, and portions of the respective needle and pipe membersadjacent the junction therebetween are welded to each other by heatgenerated due to electric resistance between both the end faces. It isnecessary for the butt welding, however, to apply force to the pipemember and the needle member along an axis common to them during thewelding operation such that the pipe member and the needle member areurged against each other. Because of such force, melted material tendsto be forced out to form flash, so that a step of trimming is requiredafter the welding operation. This trimming operation is troublesomebecause the surgical needle is very small in diameter, resulting in anincrease of the manufacturing cost. Moreover, the melted metal flowsunder the urging force also into the hollow portion of the pipe member,so that variation occurs in the depths of the bores in the respectivesurgical needles, which bores are formed respectively by the hollowportions of the pipe members.

Additionally, as the relevant prior art, there is Japanese PatentApplication Laid-Open No. 61-45745 corresponding to U.S. Ser. No.632,343 filed on July 19, 1984, which discloses coloring of surgicalneedles. In this connection, there is also U.S. Ser. No. 905,521 filedon Sept. 10, 1986 in the name of the same assignee as this application.

Japanese Patent Publication No. 58-39544 and Japanese Patent ApplicationLaid-Open Nos. 49-61980 and 50-119487 disclose a technique in which thesuture is drawn out of the surgical needle in order to simplify andfacilitate separation between the surgical needle and the suture afterthe suture has been pierced through a bodily tissue at the surgicaloperation. Japanese Utility Model Application Laid-Open No. 61-109505discloses a technique in which a part of the suture adjacent thesurgical needle is weakened locally. Furthermore, Japanese Utility ModelApplication Laid-Open No. 61-109506 discloses a technique in which thesuture is connected to the surgical needle by a special connectorelement.

Japanese Utility Model Publication No. 60-25219 discloses a techniquefor annealing the proximal end of the surgical needle formed ofaustenitic stainless steel.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a surgical needle which iseasy in manufacturing and is low in production cost.

According to the invention, there is provided a surgical needlecomprising a needle member, a pipe member arranged at a proximal end ofthe needle member and a welded portion formed between the needle andpipe members, wherein marks of welding are left as they are on thewelded portion so that the welded portion has a surface distinguishablefrom peripheral surfaces of the respective needle and pipe members.

According to the invention, there is also provided a surgical needlecomprising a needle member, a pipe member arranged at a proximal end ofthe needle member, and a plurality of peripherally spaced welded partsformed at a junction between the needle and pipe members.

According to the invention, there is further provided a method ofmanufacturing a surgical needle, comprising the steps of: abutting anend face of a pipe member against a proximal end face of a needle memberto form an abutting line which is annular in appearance; and supplying abeam energy from beam energy emitting means, toward the abutting line,from a direction substantially perpendicular to the needle and pipemembers, thereby welding the needle and pipe members to each other toform a welded portion therebetween.

According to the invention, there is provided an apparatus formanufacturing a surgical needle, comprising:

(a) beam energy emitting means;

(b) rotational support means for supporting a needle member and a pipemember in such a manner that axes of the respective needle and pipemembers extend perpendicularly to an axis of a beam energy emitted fromthe beam energy emitting means and that an end face of the needle memberand an end face of the pipe member are abutted against each other at alocation coincident with the axis of the laser beam, the rotationalsupport means also rotating the needle and pipe members about theirrespective axes; and

(c) drive means for giving rotation to the rotational support means.

According to the invention, there is also provided an apparatus formanufacturing a surgical needle, comprising a laser beam generatingsource arranged stationarily, a laser beam emitting section receiving alaser beam from the laser beam generating source through an opticalfiber, the laser beam emitting section condensing the laser beam to emitthe condensed laser beam, guide means at least including an arcuateportion, moving means for moving the laser beam emitting section alongthe guide means while maintaining such a posture that an optical axis ofthe laser beam emitted from the laser beam emitting section passesthrough a central axis of a radius of curvature of the arcuate portionof the guide means, and support means supporting the needle and pipemembers while maintaining them stationary in such a manner that theneedle and pipe members are abutted against each other at a locationsubstantially coincident with a plane including the optical axis of thelaser beam and that the axes of the respective needle and pipe membersare coincident with the central axis of the radius of curvature of theguide means.

According to the invention, there is further provided an apparatus formanufacturing a surgical needle, comprising a laser beam generatingsource arranged stationarily, dividing means for dividing a laser beamfrom the laser beam generating source into a plurality of laser beams, aplurality of laser beam emitting sections respectively receiving thelaser beams divided by the dividing means, through respective opticalfibers, to emit the respective laser beams, and support means forstationarily supporting a needle member and a pipe member in such amanner that the needle and pipe members are abutted against each otherat a location substantially coincident with a plane including opticalaxes of the respective laser beams.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view showing an embodiment of a method ofwelding a needle member and a pipe member to each other, according tothe invention;

FIG. 2 is a fragmental enlarged cross-sectional view showing the weldedportion obtained by the welding method illustrated in FIG. 1;

FIG. 3 is a plan view of a surgical needle after completion of weldingin accordance with the method illustrated in FIG. 1;

FIG. 4 is a cross-sectional view showing the welded portion of thesurgical needle illustrated in FIG. 3;

FIG. 5 is a view showing the surgical needle which is bent into a curvedform and to which a suture is attached, after completion of welding;

FIG. 6 is a fragmental enlarged schematic view showing a preferredmanner of supplying pulses of a laser beam;

FIG. 7 is a perspective view showing the needle and pipe memberstack-welded to each other, before the regular welding is carried out;

FIG. 8 is a schematic plan view showing an example of an annealingmanner after completion of welding;

FIG. 9 is a view similar to FIG. 8, but showing another example of theannealing manner;

FIG. 10 is a view similar to FIG. 8, but showing still another exampleof the annealing manner;

FIG. 11 is a schematic view showing a manner in which only amultiplicity of pipe members are annealed, the annealing being carriedout before welding;

FIGS. 12 through 15 are cross-sectional views respectively showingvarious aspects of the welded portion;

FIGS. 16 and 17 are views showing, in due order, a suture operationcarried out by the use of the surgical needle provided with one of thewelded portions shown respectively in FIGS. 12 through 15;

FIG. 18 is a view showing another aspect of a surgical needle providedwith one of the welded portions illustrated respectively in FIGS. 12through 15;

FIG. 19 is a top plan view showing an embodiment of an apparatus forcarrying out the method according to the invention, an arrangement ofrespective chuck mechanisms for a needle member and a pipe member andother mechanisms being omitted for clarification;

FIG. 20 is a cross-sectional view taken along line XX--XX in FIG. 19;

FIG. 21 is a fragmental plan view of the chuck mechanisms for therespective needle and pipe members employed in the apparatus illustratedin FIG. 19;

FIG. 22 is a front elevational view of the chuck mechanisms illustratedin FIG. 21;

FIG. 23 is an end view of the chuck mechanism for the pipe member,illustrated in FIGS. 21 and 22;

FIG. 24 is an end view of the chuck mechanism for the needle member,illustrated in FIGS. 21 and 22;

FIG. 25 is an enlarged fragmental view of a V-shaped groove illustratedin FIG. 23, the pipe member being set in the V-shaped groove;

FIG. 26 is an enlarged fragmental view of a V-shaped groove illustratedin FIG. 24, the needle member being set in the V-shaped groove;

FIG. 27 is a cross-sectional view taken along line XXVII--XXVII in FIG.19;

FIG. 28 is a cross-sectional view taken along line XXVIII--XXVIII inFIG. 19;

FIG. 29 is a partially cross-sectional enlarged fragmental view of asecond moving mechanism illustrated in FIG. 19;

FIG. 30 is a plan view of another aspect of means for supporting androtating a needle member and a pipe member;

FIG. 31 is a cross-sectional view taken along line XXXI--XXXI in FIG.30;

FIG. 32 is a front elevational view showing a surgical needlemanufacturing apparatus according to another embodiment of theinvention; and

FIG. 33 is a vertical cross-sectional view of the apparatus illustratedin FIG. 32.

DETAILED DESCRIPTION

Referring to FIGS. 1 through 5, there is shown a surgical needlemanufacturing method according to an embodiment of the invention. Asshown in FIG. 1, a straight needle member 1 and a straight pipe member 2are first prepared. These needle and pipe members 1 and 2 are formed ofaustenitic stainless steel having advantages subsequently to bedescribed. The needle member 1 has one end thereof which is formed witha planar end face 1a extending perpendicularly to an axis of the needlemember 1. The other end of the needle member 1 is formed into a pointedend 1b. The pipe member 2 is formed in the following manner. That is, arectangular strip is curled into a tubular form such that one side edgeof the strip is abutted against the other side edge. Then, the one andother side edges are welded to each other to form a tube. Subsequently,the tube is drawn through drawing dies to reduce the diameter of thetube until the diameter is brought to a value equal to the outerdiameter of the needle member 1. The diameter-reduced tube is then cutinto tube pieces each having a predetermined length. In this manner, theabove pipe member 2 is formed by each of the cut tube pieces. The lengthof the pipe member 2 is substantially equal to the depth of a bore in asurgical needle that is an intended final product. The pipe member 2 isformed at its both ends respectively with planar end faces 2a and 2bextending perpendicularly to the axis of the pipe member 2.

The needle and pipe members 1 and 2 are chucked respectively by a pairof chuck means arranged respectively on a pair of rotary structuresindependent of each other. The pair of chuck means and the pair ofrotary structures are not shown in FIG. 1, but will be described laterwith reference to FIGS. 19 through 24. When the needle and pipe members1 and 2 are chucked respectively by the chuck means, one of the planarfaces 2a of the pipe member 2 and the planar face 1a of the needlemember 1 are abutted against each other such that a single annular line3 is seen from the outside, which is formed between the respective outerperipheral surfaces of the needle and pipe members 1 and 2.

With the planar faces 1a and 2a abutted against each other, the needleand pipe members 1 and 2 are welded to each other by a laser beam Lemitted from a laser beam emitting unit 10. The laser beam emitting unit10 comprises, as its principal components, a generating source 11 of acollimated laser beam Lo, and a condenser optical system 12 including aconvex lens for condensing the collimated laser beam Lo emitted from thegeneration source 11, onto peripheral surfaces of portions of therespective needle and pipe members 1 and 2 adjacent the above-mentionedabutting line 3.

It is shown in FIG. 2 that a region on the peripheral surface of theneedle member 1, which is supplied with the condensed laser beam L, issubstantially equal in area to that on the peripheral surface of thepipe member 2, which is supplied with the condensed laser beam L.However, the laser receiving region on the needle member 1 may be largerin area than that on the pipe member 2, in consideration of the factthat the needle member 1 is larger in heat capacity than the pipe member2.

By application of the laser beam L, portions of the respective needleand pipe members 1 and 2, which are adjacent the respective end faces 1aand 2a abutted against each other, are melted. After melting, the meltedportions are cooled and solidified, thereby completing connection orwelding between the needle and pipe members 1 and 2. The welding due tothe laser beam L is carried out only at a single location on theabutting line 3, if the needle and pipe members 1 and 2 are stationary.In the illustrated embodiment, therefore, with the needle and pipemembers 1 and 2 maintained abutted against each other, pulses of thelaser beam L are successively applied to the abutting line 3 atintervals of a short period of time, while rotating the rotarystructures respectively supporting the needle and pipe members 1 and 2at the same rotational speed, thereby successively carrying out weldingalong the entire circumferential length of the abutting line 3. As aresult, as shown in FIGS. 3 and 4, a straight surgical needle 5 isformed, which is provided with an annular welded portion 4 and which isformed with a bore 5a.

The surgical needle 5 provided with the bore 5a is bent into a curvedform by a known bending device as disclosed in Japanese PatentPublication No. 60-18256. Further, with an end of a suture inserted intothe bore 5a, the proximal end of the surgical needle 5 is staked by astaking device disclosed in U.S. Pat. No. 4,722,384 or the like. As aconsequence, there is provided a curved surgical needle 7 havingattached thereto a suture 6, that is a final product as shown in FIG. 5.

In the welding described above, the energy of the laser beam L per onepulse, the time interval between each pair of adjacent pulses, a focalposition F (see FIG. 2) and the like are adjusted in such a manner thatthe penetration depth of the welded portion 4 is substantiallyconsistent with the radial wall thickness of the pipe member 2.Additionally, as shown in FIG. 2, if the focal position F of thecondenser optical system 12 is located substantially at the radialcenter or the vicinity thereof, of the radial wall thickness of the pipemember 2, the consumptive energy of the laser beam L can be reduced.

Since the laser beam L can supply energy of a controlled amount to thejunction between the needle and pipe members 1 and 2, it is possible tocarry out welding along the entire circumferential length of theabutting line 3 substantially uniformly, that is, with a constant weldpenetration depth.

It is unnecessary for the welding due to the laser beam to apply forceto the needle and pipe members 1 and 2 toward each other to therebypress them against each other. It is merely necessary to maintain theneedle and pipe members 1 and 2 abutted against each other. Accordingly,an amount by which the melted metal penetrates into the cavity withinthe pipe member 2, is extremely small, as compared with the electricresistance welding. Therefore, the cavity within the pipe member 2remains substantially unchanged as the bore 5a for attaching the suture6, making it possible to maintain the depth of the bore 5a constant.

Moreover, since the above-mentioned urging force is not applied to theneedle and pipe members 1 and 2, no flash occurs which projectsoutwardly. Rather, due to the facts that minute spaces are formedbetween the abutted end faces 1a and 2a of the respective needle andpipe members 1 and 2 by minute irregularities on the end faces 1a and 2aand by minute dust interposed between the end faces 1a and 2a, and arefilled with a part of the melted metal, and that a part of the meltedmetal is slightly drawn toward the cavity within the pipe member 2 whenthe melted metal is cooled, the welded portion 4 caves in from the outerperipheral surfaces of the respective needle and pipe members 1 and 2 byfew micron meters or to the extent slightly more than few micron meters,as shown in FIG. 3. The caving-in amount is exaggeratedly shown in FIG.3. As a result, it is possible for the invention to dispense with thetrimming step.

Since the marks of welding are left on the surface of theabove-mentioned annular welded portion 4, as shown in FIG. 5, it ispossible to distinguish, in appearance, the welded portion 4 from theperipheral surfaces of the respective needle and pipe members 1 and 2.There are two aspects of the surface of the welded portion 4.

The first aspect of the surface of the welded portion 4 is obtained inthe following manner. That is, as shown in FIG. 1, inert gas such asargon gas, nitrogen gas or the like is blown at slow speed from a pipe 8extremely small in diameter, against a region on the peripheral surfacesof the respective needle and pipe members 1 and 2, to which region thelaser beam L is applied. By doing so, the surface of the welded part 4is prevented from being oxidized and is formed into a mirror surface, sothat the surface of the welded portion 4 glistens as compared with thesurfaces of the respective needle and pipe members 1 and 2. Moreover,when the welding is carried out in a vacuum, the surface of the weldedportion 4 is likewise formed into a mirror surface.

The second aspect of the surface of the welded portion 4 is obtained insuch a manner that welding is carried out in the atmosphere without theinert gas being blown against the surfaces of the respective needle andpipe members 1 and 2. In this case, an oxide film is formed on thesurface of the welded portion 4, so that the surface of the weldedportion 4 is distinguished from the peripheral surfaces of therespective needle and pipe members 1 and 2.

The surface of the welded portion 4 cannot be vanished by electrolyticpolishing or chemical polishing, unless the surface is mechanicallyground or polished.

The ring-like welded portion 4 serves as a mark when, for example, thepipe member 2 is staked, so that it can be ensured that a part(designated by the character 2a in FIG. 5) of the pipe member 2 spaced apredetermined distance from the welded portion 4 is staked. This makesit possible to prevent occurrence of cracks or the like in the pipemember 2 due to staking of the welded portion 4 or a part very closethereto. Moreover, the ring-like welded portion 4 serves also as a markby which when a doctor clamps the surgical needle with a chuck jig at asurgical operation, he can clamp the surgical needle while keeping awayfrom the pipe member 2 which is low in strength.

It is preferable that pulses of the laser beam L are applied in a manneras shown in FIG. 6. In FIG. 6, a region of melting occurring due to asingle pulse of the laser beam L is indicated by a circle C. The pulsesof the laser beam L are successively outputted at intervals of a shortperiod of time. Since the needle and pipe members 1 and 2 are rotatedabout their respective axes simultaneously with the output of thepulses, the pulses are successively applied to the needle and pipemembers 1 and 2 along the abutting line 3 at narrow angular intervals.Thus, welded parts produced by the respective pulses are overlapped witheach other. Since a part of the needle and pipe members 1 and 2, towhich a first one of the pulses of the laser beam L is to be applied, isat the room temperature and is cool, an amount of melting at the part issmall when the laser beam L is applied to the part. Accordingly, theregion of melting appearing on the surface is narrow, and the depth ofpenetration is shallow. The depth of penetration does not reach aposition corresponding to the radial wall thickness of the pipe member2, but occupies only the outer surface layer. Thus, the welding isincomplete. A second pulse of the laser beam L is applied to a secondpart immediately adjacent the part to which the first pulse is applied,at an interval of an extremely short period of time. Since the secondpart is raised in temperature by the first pulse, the second partincreases in amount of melting when the second pulse is applied to thesecond part, so that depth of penetration increases. At a part to whicha pulse of the laser beam L subsequent to several pulses is applied, asshown in FIG. 2, the depth of penetration of the welded portion 4 issubstantially equal to the radial wall thickness of the pipe member 2,so that the welded portion 4 is locally brought to a complete weldedform. Accordingly, if it is desired to carry out the complete weldingalong the entire circumferential length of the abutting line 3, in otherwords, if it is desired that welding is carried out over the entireregion of the end face 2a of the pipe member 2, as shown in FIG. 6, thepulses of the laser beam L are again applied along the abutting line 3by a predetermined length from the part to which the first pulse isapplied.

The energy of the laser beam L may be weak at the initial few pulses. Inthis case, the energy of the laser beam L is gradually raised to asteady energy level. By doing so, the length of the initial incompletewelded part along the abutting line 3 is increased, thereby obtaining atack-welding effect. The tack-welding effect will be described later indetail with reference to FIG. 7 which remarkably shows the tack-welding.

Moreover, the pulses of the laser beam L may be applied through apredetermined length from the END position shown in FIG. 6, whilegradually weakening the energy of the laser beam L. By doing so, it ispossible to prevent a mark, like a crater, of the last pulse of thelaser beam L from being left on the welded portion 4.

By the way, when the laser beam L is applied to the junction between theneedle and pipe members 1 and 2 to successively carry out welding alongthe abutting line 3, a bending force acts to the needle and pipe members1 and 2 at the initial stage of the welding step. The bending forcetends to angularly move the needle and pipe members 1 and 2 about thepart at which welding has already been completed, so that the needle andpipe members 1 and 2 are brought into misalignment with each other. Ifthe needle and pipe members 1 and 2 are chucked respectively by a pairof chucks at respective positions remote from the abutting line 3, theneedle and pipe members 1 and 2 are subject to the bad influence of thebending force, so that there may be a case where the needle and pipemembers 1 and 2 are welded to each other while being maintainedmisaligned. This deficiency can be dissolved in the following manner.That is, prior to the regular welding, as shown in FIG. 7, a singleshort pulse of the laser beam is applied to each of a plurality of, forexample, three or more locations on the abutting line 3, which areequidistantly spaced circumferentially from each other. Since the pulsesof the laser beam are supplied respectively to the locations on theabutting line 3 under the condition that the needle and pipe members 1and 2 are at the room temperature and are cool, the depth of penetrationof each of welded parts 4' is shallow. Accordingly, substantially nobending force is produced due to the welded parts 4'. When the regularwelding is carried out as shown in FIG. 6 with the needle and pipemembers 1 and 2 tack-welded to each other, even if a bending forceoccurs temporarily due to the regular welding, the tack-welded parts 4'serve as resistance to the bending force. Thus, welding can be effectedwithout the needle and pipe members 1 and 2 being brought intomisalignment with each other.

Since the austenitic stainless steel is used as the material of theneedle and pipe members 1 and 2, the surgical needle 7 is excellent incorrosion resistance. Moreover, welding due to the laser beam L isaccompanied with local rapid heating and rapid cooling. However, theaustenitic stainless steel is not hardened by the rapid cooling, but issoftened. Therefore, it is possible to prevent occurrence of cracks inthe vicinity of the welded portion 4 due to the hardening by the rapidcooling during welding.

The welded portion 4 is soft as compared with the needle and pipemembers 1 and 2. Accordingly, when a bending force is applied to thesurgical needle 7, the needle 7 is bent at an acute angle at the weldedpart 4, so that there may be a case where cracks occur in the weldedportion 4 or the welded portion 4 is damaged. In view of this, whenwelding has been completed, as shown in FIG. 8, either one of the laserbeam emitting unit 10 and the needle and pipe members 1 and 2 is movedin a direction perpendicular to the aligned axes of the respectiveneedle and pipe members 1 and 2, thereby moving the peripheral surfacesof the respective needle and pipe members 1 and 2, away from the focalposition, that is, away from the laser beam emitting unit 10. Under thiscondition, if the laser beam L is applied to the needle and pipe members1 and 2 while rotating them, the spot area to which the laser beam L isapplied is larger than that during the welding. By this reason, a regiondesignated by the reference numeral 9 in FIG. 8, which is wider than thewelded portion 4 and which extends along the welded portion 4, isannealed at a temperature lower than the welding temperature and issoftened. Thus, when a bending force is applied to the surgical needle7, deformation occurs not only in the welded portion 4, but also in theannealing region 9, so that the surgical needle 7 is bent as a wholeinto a curved form. Accordingly, it can be ensured to prevent occurrenceof cracks in the welded portion 4 and destruction thereof.

Further, after annealing at the region 9 has been completed, the chuckis removed from the pipe member 2, and the rotary structure supportingthe needle member 1 is moved axially thereof or in a direction indicatedby the arrow in FIG. 8 while the needle member 1 is maintained chucked.At the same time, the needle and pipe members 1 and 2 are rotated abouttheir respective axes, thereby enabling the entire length of the pipemember 2 to be annealed by the laser beam L. This makes it possible toprevent cracks from occurring when the pipe member 2 is staked to attachthe suture to the surgical needle 7, and also makes it possible toincrease the attaching strength of the suture. The end of the pipemember 2 on the side opposite to the welded portion 4 may notnecessarily be softened.

Moreover, annealing may be carried out as shown in FIG. 9. That is, bymoving the needle and pipe members 1 and 2, or by moving the laser beamemitting unit 10, the peripheral surfaces of the needle and pipe members1 and 2 are moved to a position closer to the laser beam emitting unit10 than the focal position, so that the spot area increases to which thelaser beam L is applied. Other arrangement of the embodiment shown inFIG. 9 is the same as that shown in FIG. 8.

Furthermore, annealing may be effected as shown in FIG. 10. That is,after welding, a flame of a burner 10A is used to anneal the vicinity ofthe welded portion 4 and the pipe member 2.

Further, annealing may be performed as shown in FIG. 11. That is, priorto welding, a multiplicity of pipe members are wrapped up in a stainlesssteel foil 15. The pipe members wrapped up in the foil 15 are put intoan electric furnace 10B and are heated thereby. Alternatively, the pipemembers wrapped up in the foil 15 are heated from the outside by theburner shown in FIG. 10. In this manner, only the pipe members areannealed together. The volume of the multiplicity of pipe members isextremely small. For example, the volume of ten thousand pipe members isonly 1 cm³. Accordingly, the annealing method illustrated in FIG. 11makes it possible to uniformly and inexpensively anneal a large quantityof pipe members for a short period of time without the pipe membersbeing oxidized.

Welding due to the laser beam may be carried out partially with respectonly to a portion or portions of the entire region of the end face ofthe pipe member 2. For example, the welding may be carried out along theentire circumferential length of the abutting line 3 in such a mannerthat the depth of penetration is shallower than the radial wallthickness of the pipe member 2. Moreover, the welding may be carried outwith respect only to a predetermined angular extent or extents along theabutting line 3.

In each of embodiments shown respectively in FIGS. 12 through 15,welding is carried out with respect only to predetermined angularextents along the abutting line 3, in order to enable a surgical needleto have an especial function. The needle member 1 is bent into a curvedform after or before welding. In FIGS. 12 through 15, the inside of thecurved form is designated by the character "I", while the outside of thecurved form is designated by the character "0", in order to facilitateexplanation of welded positions.

In the embodiment illustrated in FIG. 12, no laser beam is applied toboth the inside "I" and the outside "0" so that two welded parts 4 and 4are formed by the laser beam. The two welded parts 4 and 4 are angularlydisplaced by 90 degrees from the inside "I" and the outside "0". Eachwelded part 4 has an angular extent of the order of 70 to 80 degrees,and has the depth of penetration of the order of a third or a fourth ofthe radial wall thickness of the pipe member 2.

In the embodiment illustrated in FIG. 13, two welded parts 4 and 4 areformed respectively in relatively narrow angular extents. The two weldedparts 4 and 4 are angularly displaced by 90 degrees from the inside "I"and the outside "0". The depth of penetration of each welded part 4 issubstantially equal to the radial wall thickness of the pipe member 2.

In the embodiment illustrated in FIG. 14, except for the outside "0" ofthe curved form, three welded parts 4 are formed respectively at threelocations circumferentially equidistantly spaced from each other. Eachof the welded parts 4 has an angular extent which is relatively small,and has the depth of penetration substantially equal to the radial wallthickness of the pipe member 2.

In the embodiment illustrated in FIG. 15, four welded parts 4 areformed. Two of the four welded parts 4 are angularly displaced by 45degrees from the inside "I", and the remaining two parts 4 are angularlydisplaced by 45 degrees from the outside "0". Each welded part 4 has arelatively small angular extent, and has the depth of penetrationsubstantially equal to the radial wall thickness of the pipe member 2.

For the surgical needle provided with the welded parts 4 in one of theembodiments illustrated respectively in FIGS. 12 through 15, it ispossible to maintain the tension strength in the direction along thealigned axes of the respective needle and pipe members 1 and 2 at asufficient level. However, the welded parts 4 are weak in bendingstrength. Such characteristic is positively utilized, thereby enablingthe following operational manner to be adopted. That is, a doctor firstclamps a portion of the surgical needle 7 adjacent the proximal endthereof, by means of a chuck jig 18. Only a clamping section of thechuck jig 18 is shown in FIG. 16. The surgical needle 7 is piercedthrough two parts of the bodily tissue cut by a bistoury. Then, thechuck jig 18 is once removed from the surgical needle 7, and againclamps a portion of the surgical needle 7 adjacent a distal end thereof.As shown in FIG. 17, with the axis of the pipe member 2 substantiallyaligned with the suture 6, the surgical needle 7 is pulled until theopposite end portions of the suture 6 coming out of the bodily tissueare brought to their respective desired lengths. Subsequently, as shownin FIG. 17, the surgical needle 7 is angularly moved through 90 degreesabout a point at which the suture 6 is connected to the pipe member 2,such that the axis of the pipe member 2 is substantially perpendicularto the suture 6. Under such condition, the doctor clamps the suture 6with fingers 19 of his hand which is not holding the chuck jig 18. Then,the doctor pulls the surgical needle 7 in the direction indicated by thearrow in FIG. 17. By doing so, a bending stress is applied to the weldedparts 4 to destroy the same, whereby the surgical needle 7 isdisassembled into the needle member 1 and the pipe member 2 havingattached thereto the suture 6. Thus, the operation of cutting the suture6 prior to the operation of tying the suture 6 can be dispensed with,making it possible to enhance the operability at the surgical operation.

It is to be noted here that, in each of the embodiments illustratedrespectively in FIGS. 12 through 15, the tension force applied to thesuture 6 acts such that one of non-welded portions is brought to thetension side. By doing so, the pipe member 2 tends to be angularly movedabout the non-welded portion, so that destruction of the welded parts 4is facilitated due to the principles of the lever. In the actual sutureoperation, the doctor's hand holding the chuck jig 18 is twistedunnaturally in the state indicated by the phantom lines in FIG. 17. Whenthe surgical needle 7 is angularly moved through 90 degrees about thepoint at which the suture 6 is connected to the pipe member 2, that is,when the surgical needle 7 is angularly moved to the position indicatedby the solid lines in FIG. 17, the doctor's hand is in the naturalstate. Accordingly, it is convenient that the outside "0" of the curvedform is brought to the tension side. To this end, it is preferable thatthe outside "0" is brought to the non-welded part, as shown in FIGS. 12through 15.

In order to show that the surgical needle can be applied to the specialsuture operational method as described above, the peripheral surface ofthe pipe member 2 may be colored by an oxidizing treatment or a platingtreatment which can be carried out after or before welding due to thelaser beam. Moreover, only a portion of the peripheral surface of thepipe member 2, which is located on the outside "0" of the curved formand which is the non-welded part, may be colored in order to indicatethe pulling direction.

The needle member 1 and the pipe member 2 may be the same in material aseach other, or may be different in material from each other. It isrequired for the needle member 1 to use material work-hardened in orderto enhance the ability of piercing into the bodily tissue. However, thematerial of the pipe member 2 may have or may not have thework-hardening ability. For example, the needle member 1 employsstainless steel of one of types SUS 302, 304 and 631 which arework-hardened. On the other hand, the pipe member 2 may use, forexample, stainless steel of type SUS 316 which is not work-hardened, inaddition to the same material as the needle member 1.

The pipe member 2 may have its outer diameter smaller than that of theneedle member 1. Moreover, such a pipe member may be employed that anouter diameter of one end of the pipe member to be abutted against theend face of the needle member is substantially equal to the outerdiameter of the needle member, and the other end of the pipe member isenlarged in diameter into a trumpet form. Alternatively, an annular stepmay be formed to enlarge the other end of the pipe member. The end ofthe suture is inserted into the enlarged other end of the pipe memberand, subsequently, the enlarged other end is staked. Accordingly, theother end of the pipe member is finally brought to an outer diameterequal to or smaller than the abutting one end of the pipe member. Priorto welding, processing or working may be applied to the inner peripheralsurface of the pipe member to form threads or irregularities forenhancing the attaching strength of the suture.

The pipe member having a considerable length may be welded to the needlemember. In this case, after the welding, the long pipe member is cut ata location spaced a desired distance from the welded portion.

The laser beam may be applied to the junction between the needle andpipe members continuously, in place of the pulses.

An electron beam may be utilized in substitution for the laser beam.When the electron beam is employed, the beam is condensed orconcentrated by an electromagnetic lens. Moreover, it is preferable thatwelding due to the electron beam is carried out in a vacuum.

The needle and pipe members may be welded to each other with a slightgap intentionally left between them.

Prior to welding of the needle and pipe members to each other, theneedle member may beforehand be bent into a curved form. Alternatively,a portion of the pipe member, into which the end of the suture has beeninserted, may beforehand be staked.

An apparatus suitable for carrying out the method described withreference to FIGS. 1 through 6 and 8 will next be described withreference to FIGS. 19 through 29.

FIG. 19 is a plan view of an apparatus 20 having a function ofsupporting the needle and pipe members 1 and 2 while rotating them. Theapparatus 20 comprises a base plate 21 which is fixedly mounted to a bed(not shown). The laser beam emitting unit shown in FIG. 1 is mounted onthe bed at a location adjacent the base plate 21, that is, at an upperlocation as viewed in FIG. 19. The laser beam emitting unit is designedto horizontally emit the laser beam whose optical axis is designated bythe character A in FIG. 19. As best shown in FIG. 20, a pair of rails 22and 22 extending parallel to the optical axis A of the laser beam arefixedly mounted to the upper surface of the base plate 21. A pair ofsliders 23 and 23 are fixedly mounted to a lower surface of a firstmoving plate 24, and are fitted respectively about the rails 22 forsliding movement therealong. Thus, the first moving plate 24 is movablein the direction along the optical axis A of the laser beam. A rail 25is fixedly mounted to the upper surface of the first moving plate 24,and extends in a direction perpendicular to the rails 22. A slider 26 isfixedly mounted to a lower surface of a second moving plate 27, and isfitted into the rail 25 for sliding movement therealong. Thus, thesecond moving plate 27 is movable in a direction perpendicular to theoptical axis A of the laser beam.

A pair of brackets 28 and 28 are fixedly mounted to the upper surface ofthe second moving plate 27. A first hollow spindle 30 is rotatablysupported by a pair of bearings 29 and 29 mounted respectively in thebrackets 28 and 28. The first spindle 30 has an axis intersected atright angles with the optical axis A of the laser beam.

On the other hand, an upstanding bracket 31 is fixedly mounted to theupper surface of the first moving plate 24. A pair of brackets 32 and 32are fixedly mounted to a side face of the bracket 31. A second hollowspindle 35 is rotatably supported by a pair of bearings 33 and 33mounted respectively in the brackets 32 and 32. The second spindle 35has an axis aligned with the axis of the first spindle 30.

Confronting forward ends 30a and 35a of the respective first and secondspindles 30 and 35 are cut out such that each of the forward ends 30aand 35a has a cross-sectional shape near a semi-circular shape, as shownin FIGS. 23 and 24. The forward ends 30a and 35a have their respectiveplanar faces 30b and 35b displaced from the axes of the respectivespindles 30 and 35, and respective planar faces 30c and 35c extendingperpendicularly to the respective planar faces 30b and 35b.

As shown in FIGS. 21, 22 and 24, a first chuck mechanism 40 forsupporting the needle member 1 is mounted to the first spindle 30. Thefirst chuck mechanism 40 has a support member 41 which is supported onthe planar face 30b of the first spindle 30 by an L-shaped bracket 42and which is fixed by screws 42a. The support member 41 is formedtherein with a V-shaped groove 41a shown in FIG. 24 and in FIG. 26 on anenlarged scale. The previously mentioned straight needle member 1 can beset in the V-shaped groove 41a. With the needle member 1 set in theV-shaped groove 41a, the axis of the needle member 1 is aligned with theaxis of the first spindle 30.

The first chuck mechanism 40 further has a retainer member 43 which issupported on the planar face 30b of the first spindle 30 by means of apin 43a for pivotal movement about an axis of the pin 43a. On the otherhand, an L-shaped leaf spring 44 (see FIG. 21) is fixed to the planarface 30c by a screw 44a. Biasing force of the leaf spring 44 is appliedto the retainer member 43 through a screw 44b threadedly engaged withthe forward end of the leaf spring 44. Thus, the forward end 43b of theretainer member 43 can retain the needle member 1 set in the V-shapedgroove 41a.

A relatively weak auxiliary leaf spring 45 is fixed by a screw 45a to aface of the retainer member 43 on the side of the support member 41, andcan lightly retain the needle member 1 set in the V-shaped groove 41a.

A chuck releasing pin 46 extends through the first spindle 30. When aforward end of the chuck releasing pin 46 pushes the rearward end 43c ofthe retainer member 43, the retainer member 43 is pivotally moved aboutthe axis of the pin 43a in the clockwise direction as viewed in FIG. 22so that the forward end 43b of the retainer member 43 is moved away fromthe needle member 1, thereby releasing the needle member 1 from thechucked state. As shown in FIG. 19, a support member 47 is screwed intothe proximal end of the first spindle 30. The chuck releasing pin 46slidably extends through the support member 47 and projects therefromoutwardly.

As shown in FIGS. 21 through 23, a second chuck mechanism 50 forsupporting the pipe member 2 is mounted to the second spindle 35. Thesecond chuck mechanism 50 has a support member 51 which is supported onthe planar face 35b of the second spindle 35 by an L-shaped bracket 52and which is fixed by screws 52a. The support member 51 is formedtherein with a V-shaped groove 51a shown in FIGS. 23 and 25, in whichthe straight pipe member 2 can be set. With the pipe member 2 set in theV-shaped groove 51a, the axis of the pipe member 2 is aligned with theaxis of the second spindle 35.

The second chuck mechanism 50 further has a retainer member 53 which issupported on the planar face 35b of the second spindle 35 by a pin 53afor pivotal movement about an axis of the pin 53a. On the other hand, anL-shaped leaf spring 54 (see FIG. 21) is fixed to the planar face 35c bya screw 54a. Biasing force of the leaf spring 54 is applied to theretainer member 53 through a screw 54b threadedly engaged with a forwardend of the leaf spring 54, whereby a face 53b of the retainer member 53can retain the pipe member 2 set in the V-shaped groove 51a.

As shown in FIG. 20, a pusher 56 having an axis aligned with theV-shaped groove 51a in the support member 51 extends through the secondspindle 35. A proximal end of the pusher 56 slidably extends through asupport member 57 fixed to the proximal end of the second spindle 35 bya set screw 57a, and projects outwardly from the support member 57. Theforward end of the pusher 56 is slidably supported by a support member58 which is fixed to the planar face 35b of the second spindle 35 bymeans of screws 58a.

As shown in FIGS. 19 and 27, a pair of brackets 60a and 60b are fixedlymounted to the upper surface of the first moving plate 24. A synchronousshaft 62 parallel to the spindles 30 and 35 is rotatably supported by apair of bearings 61 and 61 mounted respectively in the brackets 60a and60b. The synchronous shaft 62 has one end thereof to which a pulley 63is fixedly mounted by a set screw 63a. The pulley 63 is drivinglyconnected to a motor M fixedly mounted to the aforesaid bed (not shown),through a timing belt 64 and a pulley 65.

A spline 62a is formed on an axial portion of the peripheral surface ofthe synchronous shaft 62, which extends over a predetermined length. Asleeve 66 having an inner peripheral surface formed with a spline 66a ismounted on the synchronous shaft 62 for sliding movement therealong insuch a manner that the spline 66a on the sleeve 66 is in engagement withthe spline 62a on the synchronous shaft 62. A pulley 67 is fitted aboutthe sleeve 66 and is fixed thereto by means of a set screw 67a. Thepulley 67 and the sleeve 68 are biased by a spring 68 in the left-handdirection as viewed in FIGS. 19 and 27. A tube 69 having an end flangeis fixed to an end face of the pulley 67 on the side opposite to thespring 68. A bearing 70 is mounted about the tube 69. Movement of thepulley 67 and the sleeve 66 to the left-hand direction is restricted bya bifurcated fork 71 which is fixedly mounted to the second moving plate27.

On the other hand, a third pulley 73 is mounted on a portion of thesynchronous shaft 62 which is not formed with the spline 62a. The thirdpulley 73 is fixed to the synchronous shaft 62 by a set screw 73a.

As shown in FIGS. 19 and 20, a pulley 75 is fixedly mounted to the firstspindle 30 by a set screw 75a, at a location corresponding to the pulley67 on the synchronous shaft 62. The pulleys 67 and 75 are connected toeach other through a timing belt 76. As will be described later, withmovement of the second moving plate 27, the first spindle 30 as well asthe pulley 75 move. At this time, the fork 71 fixedly mounted to thesecond moving plate 27 pushes the pulley 67 to move the same.Accordingly, the relative positional relationship between the pulleys 67and 75 is maintained unchanged, making it possible to satisfactorilysecure rotative transmission through the timing belt 76.

On the other hand, a pulley 77 is fixedly mounted to the second spindle35 by a set screw 77a, at a location corresponding to the pulley 73 onthe synchronous shaft 62. The pulleys 73 and 77 are connected to eachother through a timing belt 78. The pulleys 67, 73, 75 and 77 are equalin diameter to each other. Accordingly, when the synchronous shaft 62 isrotated by the motor M, the first and second spindles 30 and 35 arerotated at the same rotational speed while the relative angularpositional relationship between the first and second spindles 30 and 35is maintained unchanged.

As shown in FIGS. 19 and 28, a sleeve 80a is fixedly mounted to theaforesaid bracket 60a. A bracket 81 is fixedly mounted to the firstmoving plate 24 at a location spaced away from the bracket 60a in thedirection perpendicular to the optical axis A of the laser beam. Anothersleeve 80b is fixedly mounted to the bracket 81. A pair of center shafts82a and 82b are supported respectively by the sleeves 80a and 80b forsliding movement therealong such that axes of the respective centershafts 82a and 82b are aligned with each other. The center shafts 82aand 82b have their respective pointed ends, and are biased toward eachother respectively by springs 83a and 83b. A positioning shaft 84 issupported between and by the pointed ends of the respective centershafts 82a and 82b for angular movement about an axis of the positioningshaft 84. An operating lever 85 is mounted on the shaft 84 for angularmovement therewith. A positioning lever 86 is also mounted on the shaft84 for angular movement therewith. In FIG. 28, the positioning lever 86and the operating lever 85 are shown as having their respectiveattaching angles equal to each other, in order to facilitateunderstanding of the construction. In practice, however, the positioninglever 86 and the operating lever 85 are angularly displaced in attachingangle from each other by 90 degrees, as shown in FIG. 19. A cam follower87 is rotatably mounted on the shaft 84. On the other hand, a bracket 88is fixedly mounted to the first moving plate 24. A face cam 89 is fixedto the bracket 88 by a set screw 89a. The shaft 84 extends through thecenter of the face cam 89. The cam follower 87 is abutted against a camface of the face cam 89.

Normally, as shown in FIG. 19, the positioning lever 86 is in avertically upstanding position, while the operating lever 85 is in ahorizontal position. When the operating lever 85 is angularly movedabout the axis of the shaft 84 by 90 degrees to a vertically upstandingposition, the positioning lever 86 is angularly moved to a horizontalposition facing toward the spindles 30 and 35. During this angularmovement, the cam action between the face cam 89 and the cam follower 87causes the positioning lever 86 to be moved in the left-hand directionas viewed in FIGS. 19 and 28, while the positioning lever 86 isangularly moved such that a positioning face 86a at the forward end ofthe positioning lever 86 approaches the forward end of the secondspindle 35. Finally, the positioning face 86a is brought to a positioncoincident with a vertical plane including the optical axis A of thelaser beam.

As shown in FIG. 19, a pair of brackets 90a and 90b are fixedly mountedto the base plate 21. A cam shaft 92 is rotatably supported by a pair ofbearings 91 and 91 mounted respectively in the brackets 90a and 90b. Thecam shaft 92 has one end thereof to which a pulley 93 is fixedlymounted. The pulley 93 is drivingly connected to the motor M (see FIG.27) through a timing belt and a pulley (both not shown).

The pulley 93 on the cam shaft 92, which is drivingly connected to themotor M, has a diameter five times that of the pulley 63 on theaforementioned cam shaft 62. With such arrangement, the cam shaft 92makes one revolution while the synchronous shaft 62 makes fiverevolutions. The cam shaft 92 serves as a driving source for a firstmoving mechanism 100 for moving the first moving plate 24, a secondmoving mechanism 110 for moving the second moving plate 27, and a thirdmoving mechanism 120 for moving the aforesaid chuck releasing pin 46.

The first moving mechanism 100 will be described with reference to FIG.19. A plate cam 101 is fixedly mounted to the cam shaft 92. On the otherhand, a bracket 102 is fixedly mounted to the lower surface of the baseplate 21. An auxiliary shaft 104 is rotatably supported by a pair ofbearings 103 which are mounted respectively in the bracket 102 and theaforesaid bracket 90b.

An elongated link 105 has one end thereof fixedly mounted to theauxiliary shaft 104, and extends therefrom vertically upwardly. A camfollower 106 is supported at a longitudinally intermediate portion ofthe link 105. A threaded shaft 107b has one end thereof fixed to theother upper end of the link 105. A link 90c is fixedly mounted to thebracket 90b, and extends therefrom vertically upwardly. A threaded shaft107a has one end thereof fixed to the upper end of the link 90c. A coilspring 107 is interposed under tension between the pair of threadedshafts 107a and 107b to bring the cam follower 106 into contact with thecircumferential surface of the plate cam 101.

A link 108 has one end thereof fixedly mounted to the auxiliary shaft104, and extends therefrom vertically upwardly. The link 108 is formedwith a cam face 108a extending vertically. On the other hand, a bracket109 is fixedly mounted to the lower surface of the first moving plate24. A cam follower 109a is rotatably supported at the forward end of thebracket 109. The first moving plate 24 is biased upwardly as viewed inFIG. 19 by a spring (not shown). The spring brings the cam follower 109ainto contact with the cam face 108a on the link 108.

In the above-described first moving mechanism 100, during one revolutionof the cam shaft 92, the cam action between the plate cam 101 and thecam follower 106 causes the auxiliary shaft 104 to be angularly movedabout its own axis in a reciprocative manner within a predeterminedangular extent. By this reciprocative angular movement, the cam actionbetween the cam face 108a and the cam follower 109a causes the firstmoving plate 24 to be once reciprocated along the optical axis A of thelaser beam. The timing of this reciprocative movement will be describedlater.

The second moving mechanism 110 will next be described with reference toFIGS. 19 and 29. A plate cam 111 is fixedly mounted to the cam shaft 92.On the other hand, an auxiliary shaft 112 is fixedly mounted, in acantilevered fashion, to the bracket 90a fixed to the lower surface ofthe base plate 21. A link 113 has one end thereof mounted on theauxiliary shaft 112 for pivotal movement about an axis thereof, andextends vertically upwardly from the auxiliary shaft 112. A cam follower113a is rotatably supported at a longitudinally intermediate portion ofthe link 113. Another link 114 is fixedly mounted to the bracket 90a,and extends therefrom vertically upwardly. A threaded shaft 104a has oneend fixed to the upper end of the link 114, and extends therefromhorizontally. A coil spring 115 is interposed under tension between theshaft 114a and the other upper end of the link 113, to bring the camfollower 113a into contact with the peripheral surface of the plate cam111. The link 113 is formed therein with a slot 113b extendingvertically. A slider 116a mounted to one end of a rod 116 is slidablyfitted into the slot 113b. The other end of the rod 116 is connected atright angles to one end of another rod 117. The other end of the rod 117is connected to one end of a bell crank 118 which is pivotally movableabout an axis of a pivot 118a. A cam follower 119 is rotatably mountedto the other end of the bell crank 118. On the other hand, the secondmoving plate 27 is biased to the left-hand direction as viewed in FIG.19 by a spring (not shown), to bring the side face of the second movingplate 27 into contact with the cam follower 119.

In the above-described second moving mechanism 110, when the cam shaft92 makes one revolution, the cam action between the plate cam 111 andthe cam follower 113a causes the link 113 to be once reciprocatedangularly within a predetermined angular extent about the axis of theauxiliary shaft 112. The reciprocative movement is transmitted to thebell crank 118 through the rods 116 and 117, so that the bell crank 118is angularly moved reciprocatively about the axis of the pivot 118a. Thereciprocative angular movement of the bell crank 118 is transmitted tothe second moving plate 27 through the cam follower 119, so that thesecond moving plate 27 is moved reciprocatively in the directionperpendicular to the optical axis A of the laser beam. The timing ofthis reciprocative movement will be described later.

The third moving mechanism 120 has a cam structure similar to the secondmoving mechanism 110. The third moving mechanism 120 will be describedbelow with reference to FIG. 19. A plate cam 121 is fixedly mounted tothe cam shaft 92. On the other hand, a link 123 has one end thereofpivotally mounted on the aforementioned auxiliary shaft 112, and extendstherefrom vertically upwardly. A cam follower 123a is rotatablysupported at a longitudinally intermediate portion of the link 123. Aspring 125 is interposed under tension between the aforesaid threadedshaft 114a and the other upper end of the link 123, to bring the camfollower 123a into contact with the peripheral surface of the plate cam121. The link 123 is formed therein with a slot (not shown) extendingvertically. A slider (not shown) mounted to one end of a rod 126 isslidably fitted into the slot. The other end of the rod 126 is connectedto one end of a bell crank 128 which is pivotally movable about an axisof a pivot 128a. A link 129 has one end thereof which is pivotallymounted to the other end of the bell crank 128. The other end of thelink 129 is pivotally connected to the aforesaid chuck releasing pin 46.

In the above-described third moving mechanism 120, when the cam shaft 92makes one revolution, the cam action between the cam plate 121 and thecam follower 123a causes the link 123 to be once reciprocated angularlywithin a predetermined angular extent about the axis of the auxiliaryshaft 112. This angular reciprocative movement of the link 123 istransmitted to the bell crank 128 through the rod 126, so that the bellcrank 128 is reciprocated angularly within a predetermined angularextent about the axis of the pivot 128a. As a result, the chuckreleasing pin 46 is once reciprocatively moved along its own axis. Thetiming of this reciprocative movement will be described later.

In the state prior to the start-up of operation of the apparatusconstructed as above, the first spindle 30 is in a position spaced awayfrom the second spindle 35. Moreover, the spindles 30 and 35 are intheir respective angular positions where the V-shaped grooves 41a and51a in the respective support members 41 and 51 are directed verticallyupwardly. Further, the chuck releasing pin 46 is in an ejected position,and the forward end 43b of the retainer member 43 is in a positionspaced away from the support member 41.

In the state described above, an operator lifts the retainer member 53up against the biasing force of the leaf spring 54 of the chuckmechanism 50. With the retainer member 53 lifted up, the operator thensets the pipe member 2 into the V-shaped groove 51a in the supportmember 51. Subsequently, the operator releases his hold from theretainer member 53 to cause the same to retain the pipe member 2 underthe biasing force of the leaf spring 54.

Then, the operator turns the operating lever 85 about the axis of thepositioning shaft 84, to bring the positioning lever 86 to a position inthe vicinity of the forward end of the support member 51 of the chuckmechanism 50. Subsequently, the operator pushes the pusher 56 to bringthe end face of the pipe member 2 into abutment against the positioninglever 86. As a result, the pipe member 2 is set at such a position thatthe one end of the pipe member 2 protrudes a predetermined length fromthe forward end of the support member 51, and the end face of the oneend of the pipe member 2 is coincident with the vertical plane includingthe optical axis A of the laser beam.

Subsequently, the operator turns the operating lever 85 about the axisof the positioning shaft 84, to return the positioning lever 86 to itsinitial upstanding position. The operator then lifts the auxiliary leafspring 45 up, and sets the needle member 1 into the V-shaped groove 41aformed in the support member 41 of the chuck mechanism 40. Subsequently,the operator releases his hold from the auxiliary leaf spring 45 tocause the same to lightly retain the needle member 1 under the biasingforce of the leaf spring 45. At this time, the end face 1a of the needlemember 1 is located adjacent the end face 2a of the pipe member 2, sothat the end of the needle member 1 projects greatly from the forwardend of the support member 41 which is in its retracted position.

After the pipe and needle members 2 and 1 have been set in the manner asdescribed above, the motor M is driven. The motor M is stopped after thesynchronous shaft 62 makes five revolutions and the cam shaft 92 makesone revolution.

The action during a period for which the synchronous shaft 62 makesfirst one-fourth revolution, will first be described. By the action ofthe second moving mechanism 110, the second moving plate 27 is moved inthe left-hand direction as viewed in FIG. 19, so that the first spindle30 and the chuck mechanism 40 are moved in the same left-hand direction.Before the synchronous shaft 62 reaches the rotational angle of theone-fourth revolution, the forward end of the support member 41 of thechuck mechanism 40 reaches a position in the vicinity of the forward endof the support member 51 of the chuck mechanism 50. At this time, thesecond moving plate 27 is stopped. In the course of this movement, theend face 1a of the needle member 1 is abutted against the end face 2a ofthe needle member 2, so that the needle member 1 is positioned. On andafter this, with movement of the chuck mechanism 40, the needle member 1slidingly moves relatively to the auxiliary leaf spring 45 and theV-shaped groove 41a. In the latter half of the first one-fourthrevolution of the synchronous shaft 62, the third moving mechanism 120causes the chuck releasing pin 46 to be moved rearwardly. After thesecond moving plate 27 is stopped, the needle member 1 is retained bythe retainer member 43 which is biased by the strong leaf spring 44.Thus, the needle and pipe members 1 and 2 are chucked in such a mannerthat the end faces 1a and 2a of the respective needle and pipe members 1and 2 are abutted against each other in the vertical plane including theoptical axis A of the laser beam. In this chucked state, the peripheralsurfaces of the respective needle and pipe members 1 and 2 are locatedadjacent the focal position of the laser beam.

During the subsequent one and one-fourth revolutions of the synchronousshaft 62, the laser beam emitting unit 10 (see FIG. 1) outputs pulses ofthe laser beam. Welding is carried out in such a manner that the pulsesof the laser beam are applied to the junction between the needle andpipe members 1 and 2 along the abutting line 3 in a partially overlappedfashion as shown in FIG. 6.

During the subsequent one-fourth revolution of the synchronous shaft 62,the first moving mechanism 100 causes the first moving plate 24 to bemoved downwardly as viewed in FIG. 19. Thus, the needle and pipe members1 and 2 are moved in the direction along the optical axis A of the laserbeam, that is, in the direction perpendicular to the aligned axes of therespective needle and pipe members 1 and 2, while the abutting line 3 ismaintained coincident with the optical axis A of the laser beam.

Subsequently, the pulses of the laser beam or the continuous laser beamis emitted from the emitting unit 10, while the synchronous shaft 62makes one revolution. The above-mentioned movement of the first movingplate 24 causes the peripheral surfaces of the respective needle andpipe members 1 and 2 to be moved away from the focal position of thelaser beam as shown in FIG. 8, so that the spot diameter of the laserbeam on the peripheral surfaces of the respective needle and pipemembers 1 and 2 increases. Accordingly, annealing is carried out alongthe welded portion over the width wider than the welded portion and atthe temperature lower than the melting temperature.

In the course of the subsequent two revolutions of the synchronous shaft62, the second moving plate 27 is moved in the right-hand direction asviewed in FIG. 19 by the second moving mechanism 110, and is returned tothe initial position. Since the biasing force of the leaf spring 44 ofthe chuck mechanism 40 is considerably stronger than that of the leafspring 54 of the chuck mechanism 50, the pipe member 2 welded to theneedle member 1 is moved together with the same in the right-handdirection as viewed in FIG. 19, and is drawn out of the chuck mechanism50. Since, during this movement of the pipe member 2, the laser beam ismaintained outputted, the peripheral surface of the pipe member 2 isannealed in a helical fashion. As a consequence, the entire peripheralsurface of the pipe member 2 is annealed.

In the course of the subsequent last one-fourth revolution of thesynchronous shaft 62, the third moving mechanism 120 causes the chuckreleasing pin 46 to be moved forwardly, that is, in the left-handdirection as viewed in FIG. 19, so that the needle member 1 is releasedfrom the chucked state due to the biasing force of the strong leafspring 44, and is retained only by the auxiliary spring 45. Moreover, inthe course of the last one-fourth revolution of the synchronous shaft62, the first moving mechanism 100 causes the first moving plate 24 tobe moved upwardly as viewed in FIG. 19, and to be returned to theinitial position.

FIGS. 30 and 31 show another embodiment of the invention, whichcomprises different arrangement for rotating the needle and pipe membersabout their respective axes. In the arrangement illustrated in FIGS. 30and 31, a bracket 200 is fixedly mounted to a moving plate (not shown).A spindle 202 is rotatably supported by a pair of bearings 201 and 201mounted in the bracket 200. A pulley 203 is fixedly mounted to theproximal end of the spindle 202, and is connected to the pulley fixedlymounted to an output shaft of a motor (not shown) through the timingbelt. A pair of chuck mechanisms for chucking respectively the needleand pipe members are mounted to the forward end of the spindle 202. Eachof these chuck mechanisms is similar in construction to the chuckmechanism 50 for the pipe member in the above-mentioned embodimentillustrated in FIGS. 21 through 23, and the detailed description andillustration of the chuck mechanisms will therefore be omitted. In FIGS.30 and 31, only support members 205 and 206 of the respective chuckmechanisms are shown. A forward end of the spindle 202 is cut out toform a planar face 202a extending parallel to the axis of the spindle202. The support members 205 and 206 are fixedly mounted to the planarface 202a, and are spaced a slight distance from each other. V-shapedgrooves 205a and 206a formed respectively in the support members 205 and206 are located in alignment with each other, so that the axes of therespective needle and pipe members set respectively in the V-shapedgrooves 205a and 206a are aligned with the axis of the spindle 202. Theforward end portion of the spindle 202 is formed therein with aplurality of bores 202b at a position corresponding to the gap betweenthe support members 205 and 206. As best shown in FIG. 31, the bores202b extend radially outwardly from the axis of the spindle 202.

In the arrangement illustrated in FIGS. 30 and 31, the forward end ofthe positioning lever (86: see FIG. 19) is moved to a position betweenthe support members 205 and 206, and the end face of the needle memberis abutted against the positioning lever and is positioned thereby. Inthis manner, the needle member is set in the V-shaped groove 205a formedin the support member 205, and is retained by the retainer member biasedby the leaf spring (not shown). Then, the positioning lever is movedaway from the gap between the support members 205 and 206 and,subsequently, the end face of the pipe member is abutted against the endface of the needle member to position the pipe member. In this manner,the pipe member is set in the V-shaped groove 206a formed in the supportmember 206, and is retained by the retainer member biased by the leafspring (not shown). Then, while rotating the spindle 202 about its ownaxis, the pulses of the laser beam from the laser beam emitting unit(not shown) are applied to the junction between the needle and pipemembers along the abutting line, to thereby carry out welding.

During application of the pulses of the laser beam, the forward endportion of the spindle 202 intercepts the optical axis of the laser beamwithin a predetermined angular extent. Since, however, the bores 202bare formed in the forward end portion of the spindle 202, the pulses ofthe laser beam can be applied to the junction between the needle andpipe members, with the result that welding can be carried outsubstantially along the entire circumferential length of the abuttingline. The laser beam emitting unit is controlled in such a synchronousmanner that the pulses of the laser beam are successively emitted eachtime the bores 202b are successively aligned with the optical axis ofthe laser beam. If it is desired to partially weld the junction betweenthe needle and pipe members only at, for example, two locations, notalong the entire circumferential length of the abutting line, the bores202b are unnecessary and are dispensed with. After the welding, themoving plate supporting the spindle 202 is moved in the direction alongthe optical axis of the laser beam in a manner similar to that of thepreviously mentioned embodiment. Subsequently, the laser beam is appliedto the welded portion while rotating the spindle 202 about its own axis,thereby carrying out annealing.

The arrangement of the embodiment illustrated in FIGS. 30 and 31 is suchthat the needle and pipe members are supported by the single spindle 202and are rotated thereby. Accordingly, as compared with the arrangementin which, as is in the previous embodiment, the needle and the pipemembers are supported respectively by the spindles 30 and 35 independentof each other and are rotated respectively thereby, it is possible forthe arrangement illustrated in FIGS. 30 and 31 to dispense with themechanism for synchronism such as, for example, the synchronous shaft 62and the associated components. It is needless to say that thearrangement illustrated in FIGS. 30 and 31 can be applied to the methodin which welding is carried out only at a plurality of locations on theabutting line, like the previous embodiment shown in FIGS. 19 through29.

FIGS. 32 and 33 show still another embodiment of the invention, in whichwhile the needle and pipe members are maintained stationary, the laserbeam emitting unit moves around the aligned axes of the respectiveneedle and pipe members. Specifically, a casing 300 has a top wallformed therein with an opening 300a. A pair of support members 301 and302 are fixedly mounted to an upper surface of the top wall of thecasing 300. The support members 301 and 302 have their respective uppersurfaces which are formed respectively with V-shaped grooves 301a and302a aligned with each other. The needle and pipe members can be setrespectively in the V-shaped grooves 301a and 302a. Positioning andchucking of these needle and pipe members are similar to those in theprevious embodiment described with reference to FIGS. 19 through 29, andthe description of the positioning and chucking will therefore beomitted. A ring-like rail 304 is fixedly mounted to the casing 300through a bracket 303. A plurality of circumferentially spaced sliders306 are fixed to the ring-like support member 305, and are supported bythe rail 304 through respective bearings or the like (not shown). Thesupport member 305 has a peripheral surface formed with teeth 305a. Agear 306a fixedly mounted to the output shaft of the motor M is in meshwith the teeth 305a of the support member 305. Accordingly, rotation ofthe motor M causes the support member 305 to be rotated. A center ofrotation of the support member 305, in other words, a center of theradius of curvature of the support member 305 is coincident with thealigned axes of the respective needle and pipe members set respectivelyin the V-shaped grooves 301a and 302a formed in the respective supportmembers 301 and 302.

On the other hand, a collimated laser beam is outputted from a laserbeam generating source 310 mounted stationarily, toward a laser beamdividing unit 311 mounted stationarily. The laser beam dividing unit 311comprises a semi-transparent mirror 312 and a mirror 313, and a pair ofcondenser optical systems 314 and 315 including their respective convexlenses optically connected respectively to the mirrors 312 and 313. Onlyhalf the collimated laser beam generated at the laser beam generatingsource 310 is reflected by the semi-transparent mirror 312, and isdirected toward the condenser optical system 314. The laser beam iscondensed by the condenser optical system 314, and is supplied to oneend of an optical fiber 316. The remaining half of the collimated laserbeam transmitted through the semi-transparent mirror 312 is reflected bythe mirror 313 and is directed to the second condenser optical system315. The laser beam from the mirror 313 is condensed by the condenseroptical system 315, and is supplied to one end of a second optical fiber317. The other ends of the respective optical fibers 316 and 317 areconnected respectively to a pair of laser beam emitting sections 320 and320. The pair of laser beam emitting sections 320 and 320 arecircumferentially spaced 180 degrees from each other so that they faceeach other. Each laser beam emitting section 320 comprises a casing 321fixedly mounted to the support member 305, and a condenser opticalsystem 322 including a convex lens fixed to the casing 321. The otherends of the respective optical fibers 316 and 317 extend through therear walls of the respective casings 321, and face the respectivecondenser optical systems 322 and 322, to supply the laser beamsthereto. Each condenser optical system 322 condenses the correspondinglaser beam to supply the same onto the abutting line between the needleand pipe members. Each laser beam has an optical axis intersected withthe aligned axes of the respective needle and pipe members.

The arrangement of the embodiment illustrated in FIGS. 32 and 33 is suchthat while angularly moving the support member 305 by the motor M aboutthe aligned axes of the respective needle and pipe members, therespective laser beams from the pair of facing laser beam emittingsections 320 and 320 are simultaneously supplied onto the abutting line.With such arrangement, if it is desired to weld the needle and pipemembers to each other along the entire circumferential length of theabutting line, it is sufficient to angularly move the support member 305substantially through 180 degrees or through an angular extent slightlylarger than 180 degrees.

Three or more laser beam emitting sections may be mounted to the supportmember 305. In this case, if it is desired to carry out welding alongthe entire circumferential length of the abutting line, it is possibleto further narrow the angular extent through which the support member305 is angularly moved. Moreover, only a single laser beam emittingsection may be mounted to the support member 305.

When it is desired to carry out welding only at a plurality of locationsspaced from each other along the abutting line, it is not required forthe support member to be angularly moved about the aligned axes of therespective needle and pipe members, but the support member may be fixedto the casing, if a plurality of laser beam emitting sectionscorresponding in number to the locations to be welded are mounted to thesupport member.

What is claimed is:
 1. A surgical needle comprising a needle member, apiper member arranged at a proximal end of said needle member and awelded portion formed between said needle and pipe member, wherein saidwelded portion caves in from the peripheral surfaces of said pipeelement and said needle element, forming a recessed annulus at saidwelded portion.
 2. A surgical needle according to claim 1, wherein saidwelded portion has a mirror-like surface which distinguishes said weldedportion from said pipe member and said needle member.
 3. A surgicalneedle according to claim 1, wherein said welded portion has an oxidefilm surface which distinguishes the surface of said welded portion fromthe surfaces of said pipe member and said needle member.
 4. A surgicalneedle according to claim 1, wherein said needle member is bent into acurved form, said welded parts being formed except for a region locatedon the outside of said curved form.
 5. A surgical needle according toclaim 1, wherein said pipe member is colored.